There are a few minor restrictions on the types
of tables that can be partitioned; for example, a table containing a LONG or LONG RAW column
cannot be partitioned. The LONG restriction should rarely be a problem; LOBs (CLOBs and
BLOBs, character large objects and binary large objects) are much more flexible and encompass
all the features of LONG and LONG RAW datatypes.
TIP
Oracle Corporation recommends that any table greater than 2GB in
size be seriously considered for partitioning.
No matter what type of partitioning scheme is in use, each member of a partitioned table
must have the same logical attributes, such as column names, datatypes, constraints, and so forth.
The physical attributes for each partition, however, can be different depending on its size and
location on disk. The key is that the partitioned table must be logically consistent from an
application or user point of view.
Chapter 1: Getting Started with the Oracle Architecture 15
Range Partitions A range partition is a partition whose partition key falls within a certain range.
For example, visits to the corporate e-commerce website can be assigned to a partition based on
the date of the visit, with one partition per quarter. A website visit on May 25, 2004, will be
recorded in the partition with the name FY2004Q2, whereas a website visit on December 2,
2004, will be recorded in the partition with the name FY2004Q4.
List Partitions A list partition is a partition whose partition key falls within groups of distinct
values.
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